he paper reports two platforms for fast diagnosis of infectious diseases using enabling bio-MEMS (bio-micro-electro-mechanical-systems) technology. The first platform uses molecular biology techniques for DNA-based diagnosis. An integrated microfluidic chip capable of performing DNA/RNA amplification, electrokinetic sample injection and separation, and on-line optical detection of nucleic acid products is developed. To demonstrate the functionality of this platform, RNA-based detection for Dengue 2 virus has been preformed in an automatic format with less sample and reagent volumes in a shorter period thanks to lower thermal inertia of the micro systems. The second platform uses ELISA (enzyme-linked immunosorbent assay) techniques for disease detection by employing an enzyme label for detection of antibody-antigen complexes. An automatic disease diagnosis system could be realized by integrating micropumps and microvalves. HCV (hepatitis C virus) and syphilis serum samples are successfully tested on the developed chips using ELISA procedure. These two bio-MEMS platforms could be crucial for molecular biology, genetic analysis, infectious disease detection, and other biomedical applications